Loading system and method for loading packaged items

ABSTRACT

A loading, picking or sorting system and a method for loading, picking or sorting packaged items, include a removal device for removing packaged items provided in a warehouse, a buffer device for buffering the removed packaged items, and a dispensing device for withdrawing buffered packaged items from the buffer device according to a particular loading order for outputting to a processing unit handling the packaged items in order to complete the loading order. In order to achieve low production, operating, and maintenance costs, the buffer device includes at least one collecting conveyor on which the buffered packaged items are collected.

The invention relates to a picking system for picking packaged items according to the preamble of claim 1 and to a method for picking packaged items according to the preamble of claim 12.

Picking systems for picking packaged items, in which the packaged items, after having been removed from a warehouse, in particular a high-rack warehouse, are stored for a certain period of time in a buffer device, and from there they are withdrawn in accordance with a present picking order to compile a shipping unit, are already known. The buffer device is formed as a high rack, wherein the packaged items are transported into the high rack lying individually or in layers on pallets or trays.

A buffer device of this type in the form of a high rack requires a large amount of space within a distribution center and is costly. High racks conventionally have a standard shelf height, wherein the available buffer space is used inefficiently in the case of packaged items that are smaller than the shelf height. In addition, the buffer device is dimensioned in accordance with a peak utilization of the picking system, since a large number of tray storage spaces are provided (typically between 100,000 and 500,000 spaces). To automate the picking orders, the known buffer devices also have automatic small part stores and/or are equipped with a complex conveying system, for example in the form of carriers (or what are known as “shuttles”) moving to and fro between the individual storage spaces and a dispensing point. To withdraw the packaged items from the buffer device in accordance with the order, wherein packaged items are exchanged between high-rack lanes and/or are sequenced in a specific succession in accordance with a picking order, a complex control system has to be provided. To ensure uninterrupted processing of the picking orders in the event of a failure of part of the conveying system, packaged items have to be stocked in multiple quantities for redundancy reasons.

The object of the invention is to provide a picking system of the generic type with a buffer device, by means of which low production, operating and maintenance costs can be achieved.

This object is achieved by a picking system according to claim 1 and by a method as claimed in claim 12.

Starting from a picking system for picking packaged items, said picking system comprising a removal device for removing packaged items that are provided in a warehouse, a buffer device that is provided for buffering the removed packaged items, and a dispensing device by means of which buffered packaged items are withdrawn from the buffer device in accordance with a picking order and are dispensed to a processing unit handling the packaged items to complete the picking order, it is proposed that the buffer device has at least one collecting conveyor, on which the buffered packaged items are collected. A compact design of the buffer device can thus advantageously be achieved. In particular, it is possible to dispense with the costly provision of individual spaces for the packaged items, for example in the form of a high rack. A “packaged item” is to be understood in particular to mean a unit that encloses at least one object to be shipped or a set of preferably identical objects to be shipped. For example, the packaged item may be formed as a commercial packaging unit or as a packet. Within the context of the invention, a “picking order” is to be understood in particular to mean an order that specifies a compilation of packaged items to form one or more shipping units. The picking order preferably specifies the type, the number and/or the succession of the packaged items forming the shipping unit.

The picking system according to the invention expediently concerns a method that is referred to by a person skilled in the art as “full case picking” and is based on the handling of packaged items from the point of removal from the warehouse until the point of provision as a shipping unit.

A “collecting conveyor” is to be understood in particular to mean an apparatus that has at least one collecting surface for receiving the buffered packaged items and a conveying unit, which conveys the buffered packaged items from an interface formed by the removal device to an interface formed by the dispensing device. As a result of this double function of the collecting conveyor as a buffer device and as a conveying device, the use of costly trays can be saved. In this case, the buffer process can be independent of the type and status of the packing process to an increased extent. Due to the proposed embodiment of the buffer device, it is also possible to dispense with a costly control system, which is necessary for a conventional withdrawal of packaged items from individual stores. In particular, the collecting conveyor may have a belt conveyor as a conveying unit, wherein further embodiments are conceivable, for example in the form of chutes or gravity roller conveyors.

Once removed from the warehouse, which is used in particular to store the packaged items in their supplied state, such as in the form of pallets in particular, the packaged items remain in the buffer device for a buffer period, which is dependent in particular on a current processing of picking orders by the processing unit. The collecting conveyor, as part of a buffer device, thus differs from a simple conveying unit, of which the function merely lies in conveying packaged items from a first point of the picking system to a further point of the picking system. At least for some of the packaged items buffered in the buffer device, the duration of the buffering corresponds preferably at least to the period of time or at least to a substantial part of the period of time, necessary to collect a certain number of packaged items on the collecting conveyor. The buffered packaged items may remain on the collecting conveyor for longer than this period of time, whilst further packaged items are processed by the processing unit. In this case, the packaged items remain on the collecting conveyor until they are dispensed, depending on the processing of picking orders from the processing unit, by the dispensing unit to the processing unit to complete the picking order to which they are assigned. The buffered packaged items can be stored on the collecting conveyor statically, that is to say in particular in an unmoved state relative to a main structure of the picking system, at least for part of the buffer period.

In particular, the processing unit has at least one unit, such as a packing station, which, on the basis of the packaged items withdrawn from the collecting conveyor, provides a shipping unit to be shipped to the corresponding ordering party of the picking order. In this unit, shipping units, for example in the form of a pallet, a trolley, etc., are compiled in accordance with what is known as the “mixed palletizing” method for example, wherein one or more shipping units correspond to a specific picking order.

In a preferred embodiment of the invention, it is proposed for the picking system to have a conveying unit that conveys the packaged items removed from the warehouse on the collecting conveyor in an orderless manner. Buffering with a high density of packaged items can thus be achieved, wherein an available buffer space can be used efficiently. An “orderless” arrangement of packaged items on the collecting conveyor is to be understood in particular to mean an arrangement in which there is no stipulation of a specific orientation with respect to the material flow, a specific spacing between two adjacent packaged items and/or a specific succession, and there are no corresponding means for providing a specific orientation, a specific spacing and/or a specific succession. In an orderless arrangement of packaged items, the packaged items advantageously have any orientation with respect to the material flow, any succession and/or any spacing from adjacent packaged items. The collecting conveyor is in this case advantageously designed in terms of a typical dimensioning of the packaged items to be handled, in such a way that it enables removal of packaged items overlapping in a direction perpendicular to the direction of material flow. If the collecting conveyor has a conveying unit with a controllable drive, a high packaged item density can be achieved in conjunction with sensor technology, visual detection systems, etc., even with a large number of packaged items.

In addition, it is proposed for the picking system to have a separating device, which is assigned to the collecting conveyor, is formed as part of the processing unit and is used to separate the packaged items withdrawn from the collecting conveyor, whereby efficient processing of picking orders can be achieved by the processing unit. A “separating device” is understood in particular to mean a device that is used to process a set of packaged items in such a way that the separated packaged items are arranged predominantly one after the other, in particular exclusively one after the other, in the direction of material flow, preferably with a spacing between two adjacent packaged items. This is suitable in particular with an orderless arrangement of packaged items on the collecting conveyor, in which packaged items overlap in a direction perpendicular to the direction of material flow.

If the buffer device is designed to buffer the removed packaged items on the collecting conveyor by means of a compilation based on a specific picking order, the picking order can be processed quickly and efficiently by the processing unit. In this case, packaged items that advantageously correspond at least to the compilation of a shipping unit in accordance with the specific picking order or the shipping unit are buffered on the collecting conveyor. This, in particular, constitutes an advantage over conventional buffer devices, in which packaged items are buffered in individual stores without reference to a specific picking order and are only compiled to produce a shipping unit by drawing individual packaged items from different individual stores. The collecting conveyor in the proposed embodiment can be denoted by the term “order-based collecting conveyor”.

It is also proposed for the picking system to have at least one time-based collecting conveyor, which is used in at least one operating mode to receive packaged items so as to provide these for assignment to a subsequent processing of a picking order. A procedure for removal of packaged items from the warehouse can thus be carried out particularly efficiently. This can be carried out in particular in view of subsequent picking orders, the processing of which is scheduled at a later time. If there is an increased need for specific goods for a subsequent time window, that is to say with regard to picking orders that are scheduled for processing at a later time, larger quantities of these goods can be removed from the warehouse, wherein packaged items that are not required for the processing of current picking orders can be placed ready on the time-based collecting conveyor. In contrast to an order-based collecting conveyor, the compilation of packaged items on the time-based collecting conveyor is not defined by a specific picking order to be processed currently. The time-based collecting conveyor may be provided in addition to at least one collecting conveyor of the buffer device. Alternatively, it may correspond to the at least one collecting conveyor of the buffer device, wherein this collecting conveyor can be used as an order-based collecting conveyor or as a time-based collecting conveyor as required. If the packaged items on the time-based collecting conveyor(s) are required for picking orders that are to be processed, the packaged items are thus sorted onto the order-based collecting conveyors after corresponding separation.

In an advantageous embodiment of the invention, it is proposed for the picking system to have an orienting unit, which is assigned to the collecting conveyor, is formed as part of the processing unit and is designed to move the packaged items withdrawn from the collecting conveyor to achieve a target orientation with respect to the material flow, whereby quick and efficient processing can be achieved by the processing unit. This is suitable in particular with an orderless arrangement of packaged items on the collecting conveyor, in which the packaged items are arranged with no orientation, that is to say without predefined orientation with respect to the material flow. The orienting unit may advantageously be formed in one piece with a separating device.

Quick processing of buffered packaged items can also be achieved if the picking system has an optical detection unit, which is formed as part of the processing unit and is designed to detect a position of packaged items relative to one another and/or relative to a predefined direction, preferably relative to the direction of material flow. The detection unit may advantageously be formed as part of a separating and/or orienting unit.

In a further embodiment, the picking system particularly preferably has a sequencing device, which is formed as part of the processing unit and which provides the packaged items withdrawn from the collecting conveyor in a succession in accordance with a present picking order.

In accordance with a development of the invention, it is proposed for the buffer device to have a set of collecting conveyors, whereby increased versatility in the processing of picking orders can be achieved. A corresponding embodiment of the invention in which collecting conveyors of the set of collecting conveyors are each assigned to a different picking order, in at least one operating mode, is particularly advantageous. In this case, these collecting conveyors are advantageously used as order-based collecting conveyors. In particular, packaged items from a collecting conveyor can be removed by the dispensing device whilst buffering of packaged items occurs on further collecting conveyors, and therefore packaged items can be fed to the processing unit as continuously as possible. Collecting conveyors within the set of collecting conveyors can also be used in a versatile manner as time-based collecting conveyors.

It is further proposed for the picking system to comprise a sorting device, which is used to sort the packaged items removed from the warehouse for buffering into the corresponding collecting conveyors. An assignment of packaged items, which have been removed from the warehouse, to a specific collecting conveyor and/or an automatic placement of packaged items on the corresponding collecting conveyor can thus advantageously be implemented in an automated manner. In this case, the sorting device may have sorting means, which are used to discharge packaged items, such as transferers, pushers, lifts, cross-belts, shoe-like sorting elements or tilting sorting elements, and by means of which the packaged items are deposited on the corresponding collecting conveyors. These sorting means expediently have at least one drive, by means of which the packaged items are advanced to the corresponding collecting conveyor.

Exemplary embodiments of the invention will be described hereinafter on the basis of the drawing, in which:

FIG. 1 shows a schematic view of a picking system according to the invention, with a warehouse, a sorting device, a buffer device comprising collecting conveyors, and a processing unit, which has a separating device, an orienting unit and a packing station,

FIG. 2 shows a three-dimensional view of an alternative picking system, and

FIG. 3 shows a schematic view of the picking system from FIG. 1 in an alternative embodiment.

FIG. 1 shows a schematic view from above of a picking system 10 of a distribution or shipping center. This system has a removal device 12, which is used to remove packaged items 14 from a warehouse 16. The warehouse 16 is formed as a high-rack warehouse, which comprises a plurality of rack storage units 16.1, 16.2, 16.3. The packaged items 14 are preferably stored in these rack storage units directly after their delivery to the distribution center. For example, pallets 18 are stored in the warehouse 16, on which the packaged items 14 are bundled together in the conventional manner. Reference sign 14 is used consistently to denote the individual packaged items, wherein the packaged items 14 may differ from one another in terms of their shape, their weight, packaging material, etc.

The removal device 12 comprises means 20 for depalletizing packaged items 14, that is to say for removing individual packaged items 14 from the pallets 18. The means 20 can be used for automated, in particular fully automated, depalletizing and/or placing of the packaged items 14 on a conveyor 22, which is suitable in particular for packaged items 14 that are required to complete a picking order at a high rate of number of items per unit of time. For packaged items 14 that are required at a lower frequency in the production of picking units and/or that can only be removed from a pallet with great effort, the depalletizing process may be implemented manually. In this case, conventional methods can be used, such as light-assisted or speech-assisted methods (“pick by light” or “pick by voice”), wherein the packaged items 14, after having been removed manually by a member of staff, are placed or deposited on the conveyor 22, for example a belt conveyor (for example in accordance with what is known as the “pick-to-belt method”).

The packaged items 14 removed from the warehouse 12 are conveyed by means of the conveyor 22 to a sorting device 24, in which they are sorted in accordance with a specific picking order for the purposes of buffering in a buffer device 26. The buffer device 26 is arranged upstream of a dispensing device 28 along the material flow, said dispensing device withdrawing packaged items 14 from the buffer device 26 that are required for the processing of a picking order and dispensing them to a processing unit 30, which is used to complete the picking order, in particular to provide a shipping unit 32, for example in the form of a pallet.

The buffer device 26 is used to temporarily store packaged items 14 for a certain buffer period dependent on a current processing of the picking order by the processing unit 30. In accordance with the invention, the buffer device has at least one collecting conveyor 34, on which the buffered packaged items 14 are collected. In the present example, the buffer device 26 comprises a set of two collecting conveyors 34, wherein the buffer device 26 may have any number of collecting conveyors 34 (see FIG. 2). The packaged items 14 removed from the warehouse 16 are sorted by means of the sorting device 24, wherein they are each assigned to a collecting conveyor 34.1 or 34.2 in accordance with a specific picking order. Different identification means are conceivable for identifying the packaged items 14, for example the detection of a barcode, the activation of an RFID chip attached to the packaged item 14 and/or optical detection. The sorting device 24 has conveying units 36 (illustrated schematically), which are arranged upstream of a collecting conveyor 34 with respect to the material flow and are used to convey the packaged items 14 removed from the warehouse 16 to the corresponding collecting conveyor 34.1 or 34.2. The conveying units 36 can be formed for example as transferers, pushers, lifts, cross-belt sorters, as shoe sorters or tilting sorting units. In this case, the packaged items 14 are conveyed in an orderless manner on a collecting conveyor 34, wherein means for setting a predefined orientation and/or a predefined spacing between the individual packaged items 14, such as a separating and/or orienting device, are omitted. The packaged items 14 collected on a collecting conveyor 34 therefore have (any) different orientations relative to the direction of material flow 38 and (any) different positions relative to one another. Furthermore, the collecting conveyors 34 are dimensioned in such a way that packaged items 14 may overlap in a direction perpendicular to the direction of material flow 38. In other words, the packaged items 14 may be arranged side by side with respect to the direction of material flow 38 so that a high density of packaged items 14 on the collecting conveyors 34 can be achieved. To achieve an expedient accumulation density of packaged items 14 on the collecting conveyors 34, drive parameters of the conveying units 36 and/or of the collecting conveyors 34, such as a conveying speed, can be set selectively. In the considered exemplary embodiment, the collecting conveyors 34 are formed as belt conveyors, wherein further embodiments of a conveying means are also conceivable.

In the considered exemplary embodiment, the buffer device 26 is designed to buffer on a collecting conveyor 34 the packaged items 14 removed from the warehouse 16 according to a specific picking order. In this case, the packaged items 14 buffered on the collecting conveyor 34 have a compilation based on the specific picking order or on the order for a shipping unit. To this end, the collecting conveyors 34 are each assigned to a specific picking order or to an order for a shipping unit and are referred to as order-based collecting conveyors. If the completion of the picking order is scheduled in accordance with the processing unit 30 and/or if all packaged items 14 required for completion of the picking order are present on the corresponding collecting conveyor 34, the corresponding packaged items 14 are withdrawn from the corresponding collecting conveyor 34 by the dispensing device 28 and are dispensed to the processing unit 30 to complete the picking order. The packaged items 14 are preferably withdrawn in an automated manner from the buffer device 26, wherein manual withdrawal is also conceivable. The withdrawn packaged items 14 are conveyed to a unit 42, which may have different functions. The unit 42 comprises at least one separating device 44, which separates the packaged items 14 arranged in an orderless manner, possibly side by side with respect to the direction of material flow 38. As in the present exemplary embodiment in particular, the unit 42 may further have an orienting device 46, which moves the unoriented packaged items 14 to achieve a target orientation with respect to the direction of material flow 38. An optical detection unit 48 is provided to detect a position of packaged items 14 relative to one another and/or relative to a predefined direction, in particular relative to the direction of material flow 38. In the considered exemplary embodiment, the separating device 44 and the orienting device 46 are formed integrally, wherein the packaged items 14 can be separated and oriented by the same device. The unit 42 may further have a sequencing unit, which sorts the packaged items 14 in accordance with a specific sequence. This sequence may be dependent on the weight, the shape and/or other external features of the packaged items 14 and/or on a succession determined by the ordering party. The number of functions to be completed by the unit 42 is dependent on the type of packaged items 14 and/or on the current picking order, for example on specific requirements of the ordering party.

After processing by the unit 42, the packaged items 14, which are now separated and sorted, oriented and/or sequenced, possibly in accordance with type, weight, shape, etc., are conveyed to a packing station 50 so as to then be packed manually and/or in an automated manner as a shipping unit 32 on a support, such as a pallet or in a trolley.

The removal device 12, the sorting device 24, the buffer device 26 with the collecting conveyors 34, the dispensing device 28 and the processing unit 30 with the separating device 44, the orienting unit 46, possibly a sequencing device, and the packing station 50 are arranged one after the other, possibly directly one after the other, with respect to the direction of material flow 38.

A further embodiment of a picking system 10 a is shown in FIG. 2. The following description is directed primarily to the differences from the exemplary embodiment of FIG. 1 so as to avoid repetition. Components or functional units that have already been described above in terms of their design and/or functions are denoted by like reference signs for the sake of clarity, wherein the letter “a” is added in order to provide a distinction.

A three-dimensional view of the picking system 10 a is illustrated in FIG. 2. This system has a removal device 12 a, by means of which packaged items 14 are removed from a high-rack warehouse 16 a having a plurality of rack storage units 16 a.1 to 16 a.3. The removed packaged items 14 are conveyed to a buffer device 26 a by means of a conveyor 22 a. This conveyor has a plurality of sets 27 a.1 to 27 a.5 of collecting conveyors 34 a, which are arranged side by side with respect to the direction of material flow 38 a. Each set 27 a comprises a plurality of collecting conveyors 34 a, which are arranged one above the other. To sort the packaged items 14 into the corresponding collecting conveyors 34 a, a sorting device 24 a is provided and, for each set 27 a, has a conveying unit 36 a formed as an elevator device for feeding the packaged items 14 into the relevant height in an orderless manner.

The buffer device 26 a is arranged upstream of a dispensing device 28 a, which withdraws the buffered packaged items 14 from the buffer device 26 a and dispenses them to a processing unit 30 a to complete a specific picking order. The dispensing device 28 a has a spiral conveyor 29 a, by means of which packaged items 14 are transported from a collecting conveyor 34 a to the level of the processing unit 30 a. Once withdrawn from a collecting conveyor 34 a, the packaged items 14 are conveyed to a unit 42 a of the processing unit 30 a. The unit 42 a has a separating device 44 a and a sequencing device 45 a, by means of which the packaged items 14 are processed in accordance with a succession conditional on the weight, the shape, the type of packaged items 14 and/or specific requirements of the ordering party. Before sequencing, the packaged items 14 are separated by the separating device 44 a. The packaged items 14 are conveyed from the unit 42 a to a packing station 50 a, by means of which shipping units 32 (not shown) are provided.

FIG. 3 shows an alternative embodiment of the picking system 10 from FIG. 1. The following description concerns merely the differences from the above-described exemplary embodiment and reference is made to the explanations already provided.

The picking system 10 has a time-based collecting conveyor 34.2. This is used to buffer packaged items 14 before they are assigned to a later processing of a picking order. The function of the time-based collecting conveyor 34.2 will be explained on the basis of the following example. With the scheduled processing of a specific picking order, packaged items 14 are depalletized with the aid of the means 20 and are placed on the conveyor 22. This concerns packaged items 14, which are conveyed on a corresponding order-based collecting conveyor 34.1 in accordance with a target compilation based on the specific picking order, as described above. So as to optimize the depalletizing process, further packaged items 14, not required for the specific picking order to be processed currently, may also be depalletized, for example by processing a complete pallet position or a complete pallet. The additional packaged items 14 that are not assigned to the picking order to be processed currently are provided on the time-based collecting conveyor 34.2 until they are assigned to a picking order of which the processing is scheduled at a later time, and are accordingly transported on an order-based collecting conveyor 34.1 assigned to this picking order. 

1-14. (canceled)
 15. A sorting system for sorting packaged items, the sorting system comprising: a removal device configured to remove packaged items made available in a warehouse; a buffer device configured to buffer the removed packaged items, said buffer device having at least one collecting conveyor on which the buffered packaged items are collected; a dispensing device configured to withdraw the buffered packaged items from said buffer device in accordance with a sorting order; and a processing unit configured to process the packaged items dispensed from said dispensing device to complete said sorting order.
 16. The sorting system according to claim 15, which further comprises a conveying unit configured to convey the packaged items removed from the warehouse onto said at least one collecting conveyor in an orderless manner.
 17. The sorting system according to claim 15, wherein said processing unit includes a separating device associated with said at least one collecting conveyor and configured to separate the packaged items withdrawn from said collecting conveyor.
 18. The sorting system according to claim 15, wherein said buffer device is configured to buffer the removed packaged items on said at least one collecting conveyor using a compilation based on a specific sorting order.
 19. The sorting system according to claim 15, wherein said at least one collecting conveyor includes at least one time-based collecting conveyor used in at least one operating mode to receive and provide the packaged items for assignment to a subsequent processing of a sorting order.
 20. The sorting system according to claim 15, wherein said processing unit includes an orienting unit associated with said at least one collecting conveyor and configured to move the packaged items withdrawn from said at least one collecting conveyor to achieve a target orientation with respect to a material flow.
 21. The sorting system according to claim 15, wherein said processing unit includes an optical detection unit configured to detect a position of packaged items relative to one another and/or relative to a predefined direction.
 22. The sorting system according to claim 15, wherein said processing unit includes a sequencing device configured to provide the packaged items withdrawn from said at least one collecting conveyor in a succession in accordance with a specific sorting order.
 23. The sorting system according to claim 15, wherein said at least one collecting conveyor of said buffer device is a set of collecting conveyors.
 24. The sorting system according to claim 23, wherein said set of collecting conveyors includes specific collecting conveyors each assigned to at least one of a plurality of different sorting orders, in at least one operating mode.
 25. The sorting system according to claim 23, which further comprises a sorting device configured to sort the packaged items removed from the warehouse for buffering in said corresponding collecting conveyors.
 26. A method for sorting packaged items, the method comprising the following steps: removing packaged items from a warehouse; buffering the removed packaged items in a buffer device having a collecting conveyor collecting the packaged items removed from the warehouse; withdrawing the buffered packaged items from the buffer device in accordance with a specific sorting order; and processing the withdrawn packaged items to complete the sorting order.
 27. The method according to claim 26, which further comprises collecting the packaged items on the collecting conveyor in an orderless manner.
 28. The method according to claim 26, which further comprises separating the packaged items withdrawn from the buffer device to complete the sorting order. 